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		<title>three.js WebGL 2 - buffergeometry - integer attributes</title>
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		<div id="info"><a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> WebGL 2 - buffergeometry - integer attributes</div>

		<script id="vertexShader" type="x-shader/x-vertex">
			in int textureIndex;

			flat out int vIndex; // "flat" indicates that the value will not be interpolated (required for integer attributes)
			out vec2 vUv;

			void main()	{

				vIndex = textureIndex;
				vUv = uv;

				gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );

			}
		</script>

		<script id="fragmentShader" type="x-shader/x-fragment">
			flat in int vIndex;
			in vec2 vUv;

			uniform sampler2D uTextures[ 3 ];

			out vec4 outColor;

			void main()	{

				if ( vIndex == 0 ) outColor = texture( uTextures[ 0 ], vUv );
				else if ( vIndex == 1 ) outColor = texture( uTextures[ 1 ], vUv );
				else if ( vIndex == 2 ) outColor = texture( uTextures[ 2 ], vUv );

			}
		</script>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			let camera, scene, renderer, mesh;

			init();

			function init() {

				camera = new THREE.PerspectiveCamera( 27, window.innerWidth / window.innerHeight, 1, 3500 );
				camera.position.z = 2500;

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x050505 );
				scene.fog = new THREE.Fog( 0x050505, 2000, 3500 );

				// geometry

				const triangles = 10000;

				const geometry = new THREE.BufferGeometry();

				const positions = [];
				const uvs = [];
				const textureIndices = [];

				const n = 800, n2 = n / 2; // triangles spread in the cube
				const d = 50, d2 = d / 2; // individual triangle size

				for ( let i = 0; i < triangles; i ++ ) {

					// positions

					const x = Math.random() * n - n2;
					const y = Math.random() * n - n2;
					const z = Math.random() * n - n2;

					const ax = x + Math.random() * d - d2;
					const ay = y + Math.random() * d - d2;
					const az = z + Math.random() * d - d2;

					const bx = x + Math.random() * d - d2;
					const by = y + Math.random() * d - d2;
					const bz = z + Math.random() * d - d2;

					const cx = x + Math.random() * d - d2;
					const cy = y + Math.random() * d - d2;
					const cz = z + Math.random() * d - d2;

					positions.push( ax, ay, az );
					positions.push( bx, by, bz );
					positions.push( cx, cy, cz );

					// uvs

					uvs.push( 0, 0 );
					uvs.push( 0.5, 1 );
					uvs.push( 1, 0 );

					// texture indices

					const t = i % 3;
					textureIndices.push( t, t, t );

				}

				geometry.setAttribute( 'position', new THREE.Float32BufferAttribute( positions, 3 ) );
				geometry.setAttribute( 'uv', new THREE.Float32BufferAttribute( uvs, 2 ) );
				geometry.setAttribute( 'textureIndex', new THREE.Int16BufferAttribute( textureIndices, 1 ) );
				geometry.attributes.textureIndex.gpuType = THREE.IntType;

				geometry.computeBoundingSphere();

				// material

				const loader = new THREE.TextureLoader();

				const map1 = loader.load( 'textures/crate.gif' );
				const map2 = loader.load( 'textures/floors/FloorsCheckerboard_S_Diffuse.jpg' );
				const map3 = loader.load( 'textures/terrain/grasslight-big.jpg' );

				const material = new THREE.ShaderMaterial( {
					uniforms: {
						uTextures: {
							value: [ map1, map2, map3 ]
						}
					},
					vertexShader: document.getElementById( 'vertexShader' ).textContent,
					fragmentShader: document.getElementById( 'fragmentShader' ).textContent,
					side: THREE.DoubleSide,
					glslVersion: THREE.GLSL3
				} );

				// mesh

				mesh = new THREE.Mesh( geometry, material );
				scene.add( mesh );

				// renderer

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				document.body.appendChild( renderer.domElement );

			}

			function animate() {

				const time = Date.now() * 0.001;

				mesh.rotation.x = time * 0.25;
				mesh.rotation.y = time * 0.5;

				renderer.render( scene, camera );

			}

		</script>

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